The risk of a government shutdown this time around may rest on words, not dollar figures.

The plainest divide between President Barack Obama and the House Republican majority centers on controversial policy dictates laced throughout the GOP budget plan. The language to fund the government through the rest of the fiscal year restricts funding for health care, Planned Parenthood, Wall Street reform and climate change — cultural touchstones that awaken their respective political bases like nothing else.

For Democrats, who’ve already gone further on spending cuts than even they expected, the legislative riders are a step too far. They can compromise on trims, but not on principles, they say.

But House Speaker John Boehner’s Republican caucus is dug in and divided — with some members prepared to shutter the government in a drive to press ideological battles they have long fought.

And the tricky part for both sides is that, while Boehner and the president can probably do some horse-trading on money — a feat in itself — some members say no compromise is possible on bedrock beliefs like abortion and given uniform opposition to Obama’s health care law.

House Appropriations Committee Chairman Hal Rogers (R-Ky.) told POLITICO flatly Thursday that some riders will be necessary to move a seven-month budget plan through the chamber.

“As we’ve seen, many of these riders are a critical part of getting it through,” Rogers said.

Boehner’s choice is stark. He can stand with a vocal share of his caucus, determined to use the budget battle as a vehicle for choking off funding for health care, the environment and reproductive rights. Any such bill, however, could die in the Senate and elevate the odds of a shutdown, which neither Boehner nor Obama favors.

But a budget with none of the most contentious riders could leave Boehner relying on Democrats to pass the bill, an embarrassing outcome for a speaker who prides himself on reflecting the will of his members.

“They are the most pivotal” element in the talks, Rep. Rob Andrews (D-N.J.) said of the riders. “The speaker has to choose between a true bipartisan agreement and a government shutdown.”

For a party divided for weeks over the extent to which it should slash the budget, Democrats are eager for the unity that a fight over riders could bring.

There is little daylight between the White House and Democratic leaders, who have been grumbling for weeks about the lack of presidential involvement, or between the party’s liberal and moderate wings, which have also been at odds. And with the focus shifted from economic to social issues, Democrats are enjoying a cleaner line of attack, casting Republicans as extremists willing to risk a shutdown for their ideological agenda.

The White House, which has otherwise been cagey about its own demands, isn’t playing coy with Republican efforts to restrain its policy objectives.

Obama has argued that a budget measure isn’t the place for these policy debates, which press secretary Jay Carney reiterated in a statement Thursday. And White House budget director Jack Lew suggested they could threaten a deal.

“They’re more emotional, sometimes, than the individual funding levels,” Lew told reporters Wednesday at a Bloomberg Breakfast. “That’s why we were so clear right at the start that it was not acceptable to put extraneous social policy and broad policy directives in a must-fund continuing resolution. It’s not going to be acceptable to us, and we’re going to have to work our way through that.”

The only other bright lines drawn by administration officials are over education funding and, to a lesser extent, energy and transportation.

Republican leaders are quietly mulling their options for a compromise on riders, taking several steps to bolster their social conservative credentials and bring along more of their members. Implicit is that the original seven-month funding plan, which was full of riders, is a political dead end.

They are eyeing a ban on funding abortions in the District of Columbia with government money, a move that might satisfy social conservatives while nullifying Democratic opposition, since it has received Democratic votes in the past.

Boehner is also expected to move a bill shortly after the recess to cut $105 billion that conservatives have targeted as part of the health care law — a move that’s aimed at quelling concern from the right that the speaker has been soft on repealing health care as part of spending bills.

In fact, conservatives like Utah Rep. Jason Chaffetz have said they would be comfortable with the GOP moving similar measures through separate bills — which has been echoed in meetings throughout the Republican Conference.

Plus, they note Obama has signed a bill with a rider to cut off funding to shut down Guantanamo.

They’ll also have fortunate timing. Budget Committee Chairman Paul Ryan (R-Wis.) will release what is likely to be an ambitious 2012 budget around the same time Congress is dealing with the seven-month CR.

The issue is whether these measures will be enough to appease the most conservative members of the conference. Republican aides are optimistic that roughly 20 of the 54 lawmakers who voted against the CR would vote for a long-term funding measure — in other words, they think they have some leeway. They are confident that a large portion of dissenters were not voting against it because of concerns about riders.

Still, there will be pressure for Boehner to hold firm. Rep. John Campbell (R-Calif.) said there are far too many riders for the speaker to dismiss. Boehner, Campbell said, should insist on deeper spending cuts if Democrats refuse to include riders.

“Maybe the total dollar amount gets played against the riders,” Campbell said. “Are they willing to cut deeper for fewer riders? Or more riders for less deep cuts?”

He said Boehner should be willing to walk away from the negotiating table, even if it means a shutdown.

“We’ll have a lot of debates: 2012 budget, debt ceiling,” Campbell said. “I would be shocked if we don’t shut down the government on one of them.”

The rhetoric is loosening, though. Boehner said Wednesday he recognizes there are “a lot of other players” involved in the budget debate. And Rogers is sounding much more open to negotiating, saying the “legislative process is the act of getting passed what you can get passed.”

“There’s a process by which legislation has to get passed,” Rogers said. “You have to give some, and you have to take some. We’re in the process of giving and taking.”

Republicans are already compiling examples to cast Democrats as hypocrites. Obama signed the 2011 defense authorization bill after House Republicans inserted a rider forbidding money from going to close the prison at Guantanamo. That rider is likely to reappear in the next budget bill, GOP aides said. A majority aide said Democrats “don’t have a leg to stand on” after the Guantanamo change helped secure the passage of the defense bill.

The brunt of the pressure on Boehner isn’t likely to come from the 87-member freshman class, which was elected largely on a common theme: cutting government spending. In private discussions — and, to a significant degree, in their votes — freshmen have made clear that most of their class is willing to jettison controversial riders to ensure overall spending cuts.

Even socially conservative freshmen, wary about diverting attention from spending, are “the first guys to say, ‘If we do this, we lose,’” one first-term conservative told POLITICO outside the House chamber Wednesday. Veteran members of the conservative Republican Study Committee are most ginned up over cutting Planned Parenthood funding, reversing environmental regulations and starving the health care law, several freshmen said.

“I’m personally of a belief that we gotta cut spending; that’s what people sent us here to do — bring the size of government down and get people back to work,” freshman Republican Rep. Adam Kinzinger of Illinois told POLITICO. “So that’s what my focus is. And in H.R. 1, I voted for most of the riders, but my opinion, and this can vary from tactic to tactic, I just think we need to go forward and reduce the size of government and cut spending.”

Rep. Candice Miller, a Republican who represents a district in the lower peninsula of Michigan, responded simply that “the money” is what’s important to her, not add-ons to spending bills.

“When I have the opportunity [to] vote on a pro-life bill, I always do. I’d put my pro-life credentials against anybody,” she said. “But to shut the government down over the Planned Parenthood amendment would probably not be a good idea, in my mind. I really think the election is about the economy, jobs, spending.”